2,802 research outputs found
Seeing Again: Revision in the Grade Three Classroom
To gain some insight on the phenomenon of revision within the primary classroom my thesis research explored the place revision has within the grade three classroom from the perspectives of the teacher and the students. This case study design involves two grade three teachers and 12 third grade students. Three research strategies were employed throughout the duration of research: 1) semi-structured interviews with the teacher and five students to understand their interpretations and intentions of revision in general as well as revision within a particular writing activity; 2) classroom observations of writing instruction and writing activities following the process of one writing activity and; 3) analysis of students’ writing across multiple drafts. Results indicate that although revision was understood and enacted differently between the two classrooms, a strong relationship existed between the teachers’ understanding and enactment of revision and their students’ understanding and interpretation of their teachers’ beliefs of revision
Exact semi-relativistic model for ionization of atomic hydrogen by electron impact
We present a semi-relativistic model for the description of the ionization
process of atomic hydrogen by electron impact in the first Born approximation
by using the Darwin wave function to describe the bound state of atomic
hydrogen and the Sommerfeld-Maue wave function to describe the ejected
electron. This model, accurate to first order in in the relativistic
correction, shows that, even at low kinetic energies of the incident electron,
spin effects are small but not negligible. These effects become noticeable with
increasing incident electron energies. All analytical calculations are exact
and our semi-relativistic results are compared with the results obtained in the
non relativistic Coulomb Born Approximation both for the coplanar asymmetric
and the binary coplanar geometries.Comment: 8 pages, 6 figures, Revte
Pyrotechnic Switch with Fuse Function
The article will present the combination of a low-voltage fuse with a pyrotechnic switch in compact design. The limited switching capacity of the very simple pyrotechnic switch is increased considerably when combined with a fuse which has classical passive time/current characteristic and high switching capacity. FEM calculations will demonstrate the functional principle and the passive and active characteristics of functional models will be examined. Switching behaviour with different overcurrents in case of passive or active triggering will be discussed on the basis of measuring results. The behaviour of such a fuse with high impulse currents will also be presented
Quench dynamics across quantum critical points
We study the quantum dynamics of a number of model systems as their coupling
constants are changed rapidly across a quantum critical point. The primary
motivation is provided by the recent experiments of Greiner et al. (Nature 415,
39 (2002)) who studied the response of a Mott insulator of ultracold atoms in
an optical lattice to a strong potential gradient. In a previous work
(cond-mat/0205169), it had been argued that the resonant response observed at a
critical potential gradient could be understood by proximity to an Ising
quantum critical point describing the onset of density wave order. Here we
obtain numerical results on the evolution of the density wave order as the
potential gradient is scanned across the quantum critical point. This is
supplemented by studies of the integrable quantum Ising spin chain in a
transverse field, where we obtain exact results for the evolution of the Ising
order correlations under a time-dependent transverse field. We also study the
evolution of transverse superfluid order in the three dimensional case. In all
cases, the order parameter is best enhanced in the vicinity of the quantum
critical point.Comment: 10 pages, 6 figure
Genetic evidence that cellulose synthase activity influences microtubule cortical array organization
To identify factors that influence cytoskeletal organization we screened for Arabidopsis ( Arabidopsis thaliana) mutants that show hypersensitivity to the microtubule destabilizing drug oryzalin. We cloned the genes corresponding to two of the 131 mutant lines obtained. The genes encoded mutant alleles of PROCUSTE1 and KORRIGAN, which both encode proteins that have previously been implicated in cellulose synthesis. Analysis of microtubules in the mutants revealed that both mutants have altered orientation of root cortical microtubules. Similarly, isoxaben, an inhibitor of cellulose synthesis, also altered the orientation of cortical microtubules while exogenous cellulose degradation did not. Thus, our results substantiate that proteins involved in cell wall biosynthesis influence cytoskeletal organization and indicate that this influence on cortical microtubule stability and orientation is correlated with cellulose synthesis rather than the integrity of the cell wall
Potts Model On Random Trees
We study the Potts model on locally tree-like random graphs of arbitrary
degree distribution. Using a population dynamics algorithm we numerically solve
the problem exactly. We confirm our results with simulations. Comparisons with
a previous approach are made, showing where its assumption of uniform local
fields breaks down for networks with nodes of low degree.Comment: 10 pages, 3 figure
Diagnosis driven Anomaly Detection for CPS
In Cyber-Physical Systems (CPS) research, anomaly detection (detecting
abnormal behavior) and diagnosis (identifying the underlying root cause) are
often treated as distinct, isolated tasks. However, diagnosis algorithms
require symptoms, i.e. temporally and spatially isolated anomalies, as input.
Thus, anomaly detection and diagnosis must be developed together to provide a
holistic solution for diagnosis in CPS. We therefore propose a method for
utilizing deep learning-based anomaly detection to generate inputs for
Consistency-Based Diagnosis (CBD). We evaluate our approach on a simulated and
a real-world CPS dataset, where our model demonstrates strong performance
relative to other state-of-the-art models
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